Generally, medians and guard rails provide information about the road ahead to the drivers on high-speed roads, such as highways.
Thus, from the information provided by medians and guard rails, drivers can predict the shape of the road ahead and drive safely.
However, as medians and guard rails can inform the drivers about the shape of the road ahead but cannot about the accidents ahead of them, many emergency warning devices, such as No. 10-1634131 of Korean Registered Patent, were developed to inform the drivers about the emergency ahead of them in case of an accident.
The said registered patent of the Emergency Notification Alarm that is installed in regular intervals comprises
A switch that an user activates to generate an activation signal in a case of an accident; a control panel that receives the activation signal and, then, generates a control signal; a caution display unit that is made of multiple LED lights and notifies the accident by lighting up or flickering according to the control signal; and,
A solar battery that converts solar energy into electric energy and line stabilizes the converted electric energy to provide power.
Further, in the registered patent of the Emergency Notification Alarm, each emergency notification alarm unit receives an unique ID. The control panel of each unit includes the ID in the accident notification data and passes down the data in relay to other nearby emergency notification alarm units. Control panels of nearby emergency notification alarm units receive the accident notification data and transmit control signals if the data includes their IDs. If the data does not include their IDs, the data gets transmitted to other nearby emergency notification alarm units with IDs included in the accident notification data in relay. The caution display unit is comprised on the other side of the delineator's reflective panel. The delineators are attached to pillars of medians or guardrails, in which the delineators appear and disappear, similar to an antenna, with a small degree of rotation.
Thus, the Emergency Notification Alarm is comprised to inform the drivers behind about an occurred accident ahead when the switch is activated and the LED lights around the caution display unit flicker.
However, if the driver is informed of the accident ahead only by the flickering of the LED lights around the caution display unit as said above, the driver recognizes the occurrence of an accident ahead but cannot be informed of additional information, such as the location of the accident.
Thus, because the said invention cannot provide precise information, such as the direction of the highway, the exact lane, and how far ahead the accident occurred, the driver faced a problem of not knowing exactly when to slow down for the accident.